1. Field of the Invention
The present invention relates to a liquid crystal display panel, and more particularly to a liquid crystal display panel, in which a size of an anti-ESD (electrostatic discharge) circuit capable of preventing an electrostatic discharge generated during a fabrication process of the liquid crystal display panel is minimized, thereby maximizing a space section of the liquid crystal display panel.
2. Description of the Prior Art
In general, a liquid crystal display panel is a flat type display device including two glass substrates and a liquid crystal layer filled between two glass substrates. A lower substrate of the liquid crystal display panel is formed on an upper surface thereof with gate lines and data lines, which are aligned in cross to each other in order to define pixel regions. Also, a pixel electrode and a thin film transistor, which are switched by a driving signal of the gate line in order to apply a signal of the data line to the pixel electrode, are aligned in each pixel region. In addition, a black matrix is aligned on an upper glass substrate of the liquid crystal display panel so as to prevent light from radiating into regions in which pixel electrodes are not formed. Also, a color filter layer is aligned in each of the pixel regions, and a common electrode is aligned at a front surface of the upper glass substrate.
Such liquid crystal display panels mainly include a liquid crystal panel used for displaying images, in which a plurality of gate lines and data lines are aligned in cross to each other and thin film transistors are aligned at cross points of the gate lines and data lines, and a gate drive IC and a source drive IC for applying driving voltage to the gate lines and the data lines of the liquid crystal panel, respectively.
Meanwhile, such a liquid crystal display panel generates an electrostatic discharge (ESD) when manufacturing processes, such as a deposition process, an etching process, and a cell fabricating process, are carried out. The electrostatic discharge may cause a breakage of devices and insulation layers, so articles are degraded and a yield rate of the articles is reduced.
For this reason, a production line is designed to include a conductive chuck and an anti-ESD cassette for preventing ESD. Also, pixels are designed such that the electrostatic discharge can be carried out without changing the properties of thin film transistor devices and wirings, if the panel is charged with static electricity.
For example, in order to prevent electrostatic discharge fault, a liquid crystal display panel typically employs a method for dispersing electric charges by connecting the all wirings to each other by means of resistance, thereby inducing a slow discharge of static electricity, as well as a method for performing the electrostatic discharge at a wiring formed at an outer portion of a scribe line. Herein, the former method is adapted mainly for TFT-LCDs, and the latter is adapted to a passive matrix liquid crystal display panel.
That is, a shorting bar or a shorting ring is formed on a substrate of the TFT-LCD, thereby preventing a fault of TFT-LCD caused by ESD.
FIG. 1 is a view showing a structure of a conventional liquid crystal display panel.
As shown in FIG. 1, the conventional liquid crystal display panel includes a gate ESD 1 and a data ESD 3, which are bound together by a shorting bar 5, for protecting a display panel from ESD. Generally, a common signal is applied to the shorting bar 5. Herein, the gate ESD 1 and the data ESD 3 are called “inner ESDs” being opposed in conception to outer ESDs, which will be described later.
A repair line 7 having a  C-shape or a reverse  C-shape is mounted at an outside of the shorting bar 5. Also, a plurality of gate pads 9 applying a driving signal to a gate line of the display panel and a plurality of data pads 11 applying the driving signal to a data line of the display panel are provided at an outside of a thin film transistor array substrate 100.
According to the above conventional liquid crystal display panel, static electricity, which is generated from an exterior of the liquid crystal display panel, is introduced into the shorting bar 5 through an outer gate ESD 13 and an outer data ESD 15 provided at an outside of the gate pads 9 and the data pads 11. Also, such static electricity introduced into the shorting bar 5 is distributed by the shorting bar 5, so that the static electricity spreads out over the whole area of the liquid crystal display panel.
Accordingly, a voltage difference between the outside and the inside of the liquid crystal display panel is minimized. In addition, even if an electrostatic discharge is suddenly generated, a fault caused by such an electrostatic discharge may be prevented. Also, the static electricity generated from the liquid crystal display panel while a fabrication process is being carried out can be discharged from the panel through an above-mentioned path, thereby minimizing the influence of the ESD.
However, such a conventional liquid crystal display panel has problems as follows.
Sizes of inner and outer ESDs formed in the liquid crystal display panel may occupy a space of few tens of micrometers to hundreds of micrometers. Herein, as the size of the liquid crystal display panel becomes reduced or enlarged, there is necessary to provide various patterns forming the liquid crystal display panel as well as the inner and outer ESDs. However, such sizes of the inner and outer ESDs may restrict the formation of various patterns, thereby resulting various faults in a liquid crystal display panel.